Theofan Prokopovych and Georgiy Konyskyi are the most prominent professors of Kyiv-Mohyla Academy in the 18th century. Their courses (1707-09 and 1749/51) are well regarded among the researchers and translated into Ukrainian in 1980 and 1990 respectively. Both texts generally have been considered as original. However, after a careful examination, it possible to notice a strong influence of Prokopovych on Konyskyi. This publication provides a comparative critical edition of a section from both courses on the same topic, on the infinity. (...) The section is published together with the available Ukrainian translations. The four text are synchronized, so it is easy to track the same passage in all the texts. Since the texts of both authors are based on several manuscripts, the publication is accompanied with the apparatus criticus. Because there is no tradition of publishing critical editions of Latin texts in Ukraine, a detailed explanation of the rules of apparatus criticus is provided here. -/- At this stage, it is too early to give a full account of the connection between Konyskyi’s and Prokopovych’ courses; nevertheless, based on the published section, it possible to say that Konyskyi used Prokopovych text mostly verbatim. He made some structural rearrangements, added some comments and clarifications. His text sounds more logical and more easily to apprehend. Considering the main goal of teaching activity – to pass a common knowledge, clarity of explanation is a higher value, than originality. (shrink)